Okay, it doesn’t have very much to do with contracts (though it does involve sales of goods) but a new paper from the good folks at the Wharton School in their Knowledge at Wharton E-letter, tells you what you already know: people don’t like the gifts you pick out as much as they like the stuff they choose themselves.

In The Efficiency of Gift Giving: Is It Really Better to Give than to Receive?, business prof Joel Waldfogel, among other things, asks students whether they prefer the CDs their parents bought them or the ones they picked out themselves. Turns out that gift recipients value their gifts 18% less than similar goods that they bought themselves. Waldfogel told the recipients to exclude the sentimental aspects of the gift to make the comparison apples-to-apples.

Waldfogel suggests that recipients be allowed to register at stores, like newlyweds do, so that loved ones can order from items on the wish list. "Buying things without knowing what people want," he concludes, "is a recipe for buying things people don’t want."